<?php
class Foo {
    public    $p1;
    protected $p2;
    private   $p3;
}
$obj = new ReflectionObject(new Foo());
var_dump($obj->hasProperty("p1"));
var_dump($obj->hasProperty("p2"));
var_dump($obj->hasProperty("p3"));
var_dump($obj->hasProperty("p4"));
?>
     
    The above example will output
something similar to:
 
    
bool(true)
bool(true)
bool(true)
bool(false)